A case of percutaneous deep pelvic abscess drainage using CT fluoroscopic guided cranio-caudal puncture technique

A 52-year-old male patient presented with complaints of abdominal and back pain. CT revealed a deep pelvic abscess extending into the anterior sacral space. Since puncture via the conventional transgluteal approach cannot reach a deep abscess, percutaneous pelvic abscess drainage was performed under CT fluoroscopy using the cranio-caudal puncture technique. The cranio-caudal puncture requires needle insertion perpendicular to the CT cross-section. This method advances the CT gantry deeper than the needle tip and follows the CT cross-section with the needle tip. This series of images and movements continues until the needle reaches the target. The procedure was successful without complications, the abscess was reduced in size, and blood test data improved. The cranio-caudal puncture technique provides an alternative for the drainage of deep pelvic abscesses that avoids the complications associated with gluteal muscle puncture. Percutaneous drainage of pelvic abscesses under CT fluoroscopy-guided cranio-caudal puncture offers a safe option as a puncture route for deep pelvic abscesses.

Low-dose CT fluoroscopy-guided interventional minimally invasive robot

Background

This study aimed to assess the feasibility, safety, and accuracy of a low-dose CT fluoroscopy-guided remote-controlled robotic real-time puncture procedure.

Methods

The study involved two control groups with Taguchi method: Group A, which underwent low-dose traditional CT-guided manual puncture (blank control), and Group B, which underwent conditional control puncture. Additionally, an experimental group, Group C, underwent CT fluoroscopy-guided remote-controlled robotic real-time puncture. In a phantom experiment, various simulated targets were punctured, while in an animal experiment, attempts were made to puncture targets in different organs of four pigs. The number of needle adjustments, puncture time, total puncture operation time, and radiation dose were analyzed to evaluate the robot system.

Results

Successful punctures were achieved for each target, and no complications were observed. Dates were calculated for all parameters using Taguchi method.

Conclusion

The low-dose CT fluoroscopy-guided puncture robot system is a safe, feasible, and equally accurate alternative to traditional manual puncture procedures.

Helical CT versus intermittent CT fluoroscopic guidance for musculoskeletal needle biopsies: impact on radiation exposure, procedure time, diagnostic yield, and adverse events

OBJECTIVE

Image-guided percutaneous needle biopsies are essential in the workup of musculoskeletal (MSK) lesions. While helical CT (HCT) is well established, intermittent CT fluoroscopy (iCTF) is an increasingly used alternative. The purpose of this study is to establish whether differences in subject radiation exposure, procedure time, yield, or adverse events exist between HCT and iCTF guidance.

MATERIALS AND METHODS

This retrospective cohort study included consecutive MSK needle biopsies performed on a single-CT scanner over a 12-month period at a tertiary academic center. Subject demographics, radiation dose, and outcomes were abstracted from the medical record. Comparisons between the two cohorts were performed using Student's t-test for continuous data and using Fisher's exact test for categorical data and a two-tailed p value less than 0.05 was considered significant.

RESULTS

Two hundred sixteen adults (115 (53.2%) females) with a mean age of 58.8 ± 18.4 years, underwent 216 biopsies (109 (50.5%) HCT guided, 107 (49.5%) iCTF guided) between June 2017 and June 2018. Dose-length product (DLP) and volume CT dose index (CTDIvol) were significantly higher for the HCT cohort (HCT 698.9 ± 400.8 mGycm vs iCTF 312.8 ± 170.8 mGycm; p < 0.005 and HCT 19.1 mGy ± 8.8 vs iCTF 6.9 mGy ± 1.5, p < 0.001). No significant difference in diagnostic yield, procedure time, or adverse event rate was identified.

CONCLUSION

For CT-guided MSK needle biopsies, iCTF decreases subject radiation dose compared to HCT without negatively affecting outcomes. iCTF should be strongly considered by radiologists performing MSK biopsies given the reduced patient radiation exposure.

The foramen ovale "mirage" and how this impacts percutaneous cannulation for treatment of trigeminal neuralgia: a report of two cases

Percutaneous stereotactic radiofrequency rhizotomy (PSR) for trigeminal neuralgia most commonly utilizes 2D fluoroscopy for intraoperative needle guidance into the foramen ovale (FO). We describe two cases in which needle advancement into FO was unachievable despite appropriate needle placement on biplane fluoroscopy. Intraoperative multiplanar reconstruction was helpful in more accurately depicting foraminal anatomy which allowed the manipulation of the tip of the needle, which was followed by successful FO cannulation. We propose that this "mirage" is likely created by the inherent nature of X-ray-based fluoroscopy in which the FO appears to be readily penetrable, when in fact the 3D anatomy actually prevents cannulation.

Treatment under control of CT fluoroscopy]

OBJECTIVE

To demonstrate one of the effective methods of treatment of the piriformis syndrome under the control of a highly technological visualization method.

MATERIAL AND METHODS

Eight patients (7 women and 1 man), aged 44 to 63 years, with piriformis syndrome, were studied from 2016 to 2018. The main complaints of the patients were pain in the lumbosacral spine with irradiation to the gluteal region and/or legs. All patients underwent MRI and/or MSCT of the lumbosacral spine, the pelvic ultrasound, according to the results of which 1 patient was diagnosed with uterine myoma, 5 with lesions of intervertebral discs in the L4-L5 and L5-S1 segments of varying severity in combination with changes in posture. For therapeutic purposes, all patients under the control of CT fluoroscopy were administered to xeomin (n=3), dexamethasone (n=1) or betamethasone (n=4).

RESULTS

In all patients, a positive therapeutic effect was observed after 4-12 months for xeomin injections, 2-3 weeks for dexamethasone and up to 3 months for betamethasone. No complications during the manipulations were observed. The authors present a clinical case to describe the botulinum therapy technique under the control of CT fluoroscopy, which allows effective treatment of the piriformis syndrome.

CONCLUSION

In the treatment of the piriformis syndrome it is necessary to apply an integrated approach, the leading of which are methods of local impaction on the suffering muscle. Only a methodologically correct injection can increase the effectiveness of treatment in these patients and reduce the risk of complications.

Computed tomography fluoroscopy-guided cutting needle biopsy of pulmonary nodules ≤8 mm: A retrospective study including 117 nodules

PURPOSE

To evaluate the diagnostic yield and safety of computed tomography (CT) fluoroscopy-guided cutting needle biopsy (CNB) for pulmonary nodules ≤ 8 mm.

METHOD

Data of CT fluoroscopy-guided CNB for pulmonary nodules ≤ 8 mm performed in a single institution were retrospectively analyzed. One hundred and seventeen biopsy procedures for 117 pulmonary nodules (mean size, 7.4 mm) in 114 patients were included in the study. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall diagnostic accuracy were calculated. Univariate analyses were performed to elucidate the risk factors for diagnostic failure (i.e., non-diagnostic, false-positive, or false-negative results). Complications were graded per the Clavien-Dindo Classification.

RESULTS

One (0.9 %) non-diagnostic biopsy result was found. The diagnostic accuracy was 95.7 % (112/117). The sensitivity and specificity were 95.8 % (91/95) and 95.5 % (21/22), respectively. PPV and NPV were 98.9 % (91/92) and 87.5 % (21/24), respectively. Univariate analyses showed that nodules in the lower lobes (p = 0.006) and prone biopsy position (p = 0.021) were the significant risk factors for diagnostic failure. The incidence of pneumothorax requiring chest tube placement (Grade IIIa) was 6.8 % (8/117). No Grade IIIb or higher complications were observed.

CONCLUSION

CT fluoroscopy-guided CNB for pulmonary nodules ≤ 8 mm showed a high diagnostic yield without severe complications.

Analysis of Complications of Percutaneous Transthoracic Needle Biopsy Using CT-Guidance Modalities In a Multicenter Cohort of 10568 Biopsies

Objective

To analyze the complications of percutaneous transthoracic needle biopsy using CT-based imaging modalities for needle guidance in comparison with fluoroscopy in a large retrospective cohort.

Materials and Methods

This study was approved by multiple Institutional Review Boards and the requirement for informed consent was waived. We retrospectively included 10568 biopsies from eight referral hospitals from 2010 through 2014. In univariate and multivariate logistic analyses, 3 CT-based guidance modalities (CT, CT fluoroscopy, and cone-beam CT) were compared with fluoroscopy in terms of the risk of pneumothorax, pneumothorax requiring chest tube insertion, and hemoptysis, with adjustment for other risk factors.

Results

Pneumothorax occurred in 2298 of the 10568 biopsies (21.7%). Tube insertion was required after 316 biopsies (3.0%), and hemoptysis occurred in 550 cases (5.2%). In the multivariate analysis, pneumothorax was more frequently detected with CT {odds ratio (OR), 2.752 (95% confidence interval [CI], 2.325–3.258), p < 0.001}, CT fluoroscopy (OR, 1.440 [95% CI, 1.176–1.762], p < 0.001), and cone-beam CT (OR, 2.906 [95% CI, 2.235–3.779], p < 0.001), but no significant relationship was found for pneumothorax requiring chest tube insertion (p = 0.497, p = 0.222, and p = 0.216, respectively). The incidence of hemoptysis was significantly lower under CT (OR, 0.348 [95% CI, 0.247–0.491], p < 0.001), CT fluoroscopy (OR, 0.594 [95% CI, 0.419–0.843], p = 0.004), and cone-beam CT (OR, 0.479 [95% CI, 0.317–0.724], p < 0.001) guidance.

Conclusion

Hemoptysis occurred less frequently with CT-based guidance modalities in comparison with fluoroscopy. Although pneumothorax requiring chest tube insertion showed a similar incidence, pneumothorax was more frequently detected using CT-based guidance modalities.

Safety of CT-guided cervical nerve root corticosteroid injections

INTRODUCTION

Computed tomography-guided cervical nerve root corticosteroid injections are a commonly performed procedure for cervical radiculopathy. There have been major complications such as spinal cord infarction and posterior circulation stroke reported mostly with X-ray fluoroscopic-guided methods, however, there is relatively little data on the safety of newer CT-guided methods. The purpose of this study was to identify any major complications and evaluate the rate of minor complications from CT-guided cervical nerve root corticosteroid injections performed in a tertiary public hospital.

METHODS

Four hundred and three CT-guided cervical nerve root injection procedures were identified over a period from July 2015 to January 2018 using the radiology information system (RIS) and data collected about the technique and any immediate complications. Patient follow-up and delayed complications were then reviewed, either via outpatient clinic records or telephone consultation.

RESULTS

Two hundred and eighty-six procedures were performed by radiology registrars or fellows, and 117 by radiologists, most commonly via an anterolateral approach and injecting 4 mg (in 1 mL) of dexamethasone. Follow-up data were obtained for all 403 procedures and identified 16 minor complications, but no major neurovascular complications.

CONCLUSION

The overall recorded rate of minor complications with CT-guided nerve root injection was 4.0% with no major neurovascular complications, suggesting that CT-guided transforaminal cervical corticosteroid injection is a safe procedure.

Improvement of image quality and dose management in CT fluoroscopy by iterative 3D image reconstruction

OBJECTIVES

The objective of this study was to assess the influence of an iterative CT reconstruction algorithm (IA), newly available for CT-fluoroscopy (CTF), on image noise, readers' confidence and effective dose compared to filtered back projection (FBP).

METHODS

Data from 165 patients (FBP/IA = 82/74) with CTF in the thorax, abdomen and pelvis were included. Noise was analysed in a large-diameter vessel. The impact of reconstruction and variables (e.g. X-ray tube current I) influencing noise and effective dose were analysed by ANOVA and a pairwise t-test with Bonferroni-Holm correction. Noise and readers' confidence were evaluated by three readers.

RESULTS

Noise was significantly influenced by reconstruction, I, body region and circumference (all p ≤ 0.0002). IA reduced the noise significantly compared to FBP (p = 0.02). The effect varied for body regions and circumferences (p ≤ 0.001). The effective dose was influenced by the reconstruction, body region, interventional procedure and I (all p ≤ 0.02). The inter-rater reliability for noise and readers' confidence was good (W ≥ 0.75, p < 0.0001). Noise and readers' confidence were significantly better in AIDR-3D compared to FBP (p ≤ 0.03). Generally, IA yielded a significant reduction of the median effective dose.

CONCLUSION

The CTF reconstruction by IA showed a significant reduction in noise and effective dose while readers' confidence increased.

KEY POINTS

• CTF is performed for image guidance in interventional radiology. • Patient exposure was estimated from DLP documented by the CT. • Iterative CT reconstruction is appropriate to reduce image noise in CTF. • Using iterative CT reconstruction, the effective dose was significantly reduced in abdominal interventions.

Clinical utility of radiofrequency ablation following transarterial injection of miriplatin-iodized oil suspension in small hepatocellular carcinoma

PURPOSE

To retrospectively evaluate the clinical utility of radiofrequency ablation (RFA) following transarterial injection of miriplatin-iodized oil suspension (MPT-RFA) for hepatocellular carcinoma treatment.

MATERIALS AND METHODS

We evaluated clinical outcomes of MPT-RFA for three or fewer hepatocellular carcinomas. Twenty-one patients with 30 tumors (maximum diameter: mean 1.4 ± 0.4 cm, range 0.7-2.2 cm) received MPT-RFA.

RESULTS

Nineteen patients (90.5 %, 19/21) achieved complete ablation at the first RFA session. Two patients (9.5 %, 2/21) required a second RFA session but achieved complete ablation. Primary and secondary technical success rates were 90.5 and 100 %. There were no deaths related to the procedures performed. Grade 3 or 4 increases in the serum aspartate aminotransferase, alanine aminotransferase, and bilirubin levels were found in six patients (38.1 %, 8/21). There were no liver infarctions. During the median follow-up period of 24.1 months (mean ± SD 24.7 ± 6.9 months, range 13.8-38.9 months), the local tumor progression rate and overall survival rate at 2 years was 5.0 % (95 % confidence interval 0.3-20.6 %) and 86.7 % (95 % confidence interval 56.3-96.5 %), respectively. The mean hospital stay was 8.4 ± 3.1 days (range 5-18 days).

CONCLUSION

MPT-RFA is a safe therapeutic option that initially provides therapeutic results.

Technique for CT Fluoroscopy-Guided Lumbar Medial Branch Blocks and Radiofrequency Ablation

OBJECTIVE

The purpose of this study is to describe the procedure for CT fluoroscopy-guided lumbar medial branch blocks and facet radiofrequency ablation.

CONCLUSION

CT fluoroscopic guidance allows more-precise needle tip positioning and is an alternative method for performing medial branch blocks and facet radiofrequency ablation.

Reducing Patient Radiation Exposure From CT Fluoroscopy-Guided Lumbar Spine Pain Injections by Targeting the Planning CT

OBJECTIVE

CT fluoroscopy-guided lumbar spine pain injections typically include a preprocedural planning CT that contributes considerably to patient dose. The purpose of this study was to quantify the degree of radiation exposure reduction achieved by modifying only the planning CT component of the examination.

MATERIALS AND METHODS

A retrospective review was performed of 80 CT fluoroscopy-guided lumbar spine injections. Forty patients were scanned with a standard protocol using automatic tube current modulation (method A). Another 40 patients were scanned using a new technique that fixed the tube current of the planning CT to either 50 or 100 mA on the basis of the patient's anteroposterior diameter and that reduced the z-axis coverage (method B). Dose-length products (DLPs) were compared for the two methods.

RESULTS

The mean maximal tube current for the planning CT was 435.0 mA for method A and 67.5 mA for method B. The mean z-axis was shorter for method B at 6.5 cm than for method A at 9.6 cm (p < 0.0001). The mean DLP for the planning CT was 11 times lower for method B than for method A: 27.9 versus 313.1 mGy × cm, respectively (p < 0.0001). When method B was used, the mean DLP for the total procedure (i.e., planning CT plus CT fluoroscopy components) was reduced by 78%. There was no significant difference between methods A and B in CT fluoroscopy time (p = 0.37). All procedures were technically successful.

CONCLUSION

A nearly fivefold reduction in radiation exposure can be achieved in CT fluoroscopy-guided lumbar spine pain injections through modifications to the planning CT alone.

Comparison of cone-beam CT-guided and CT fluoroscopy-guided transthoracic needle biopsy of lung nodules

PURPOSE

To compare the diagnostic performance of cone-beam CT (CBCT)-guided and CT fluoroscopy (fluoro-CT)-guided technique for transthoracic needle biopsy (TNB) of lung nodules.

METHODS

The hospital records of 319 consecutive patients undergoing 324 TNBs of lung nodules in a single radiology unit in 2009-2013 were retrospectively evaluated. The newly introduced CBCT technology was used to biopsy 123 nodules; 201 nodules were biopsied by conventional fluoro-CT-guided technique. We assessed the performance of the two biopsy systems for diagnosis of malignancy and the radiation exposure.

RESULTS

Nodules biopsied by CBCT-guided and by fluoro-CT-guided technique had similar characteristics: size, 20 ± 6.5 mm (mean ± standard deviation) vs. 20 ± 6.8 mm (p = 0.845); depth from pleura, 15 ± 15 mm vs. 15 ± 16 mm (p = 0.595); malignant, 60% vs. 66% (p = 0.378). After a learning period, the newly introduced CBCT-guided biopsy system and the conventional fluoro-CT-guided system showed similar sensitivity (95% and 92%), specificity (100% and 100%), accuracy for diagnosis of malignancy (96% and 94%), and delivered non-significantly different median effective doses [11.1 mSv (95 % CI 8.9-16.0) vs. 14.5 mSv (95% CI 9.5-18.1); p = 0.330].

CONCLUSION

The CBCT-guided and fluoro-CT-guided systems for lung nodule biopsy are similar in terms of diagnostic performance and effective dose, and may be alternatively used to optimize the available technological resources.

KEY POINTS

• CBCT-guided and fluoro-CT-guided lung nodule biopsy provided high and similar diagnostic accuracy. • Effective dose from CBCT-guided and fluoro-CT-guided lung nodule biopsy was similar. • To optimize resources, CBCT-guided lung nodule biopsy may be an alternative to fluoro-CT-guided.

CT Fluoroscopy-guided Aspiration of Intracerebral Hematomas: Technique and Outcomes

Objective

The authors evaluated the feasibility and targeting accuracy of CT fluoroscopy (CTF)-guided catheter placement and aspiration of intracerebral hematoma (ICH)s.

Materials and Methods

Nine patients (mean age, 63.3 ± 15.3 years) were treated by CTF-guided hematoma aspiration under local anesthesia. The targeting errors in the lesion center, volume of the aspirated hematoma, accuracy of the final catheter position, procedure time, and clinical outcomes were evaluated.

Results

All catheters were successfully placed in the center of the hematoma. The mean volume of the aspirated hematoma was 20.6 ± 8.8 mL (pre-treatment, 44.7 ± 20.1 mL; post-treatment, 24.1 ± 13.8 mL). The average procedure time was 25.1 minutes (range, 18-32 minutes). In one case with a scanty residual hematoma, the catheter was removed at the end of the procedure. In the remaining eight cases, the catheter was left in the residual hematoma for drainage and all catheter tips were accurately located in the final position. There were no procedure-related complications, including rebleeding and infection.

Conclusion

CTF-guided ICH aspiration is a feasible, quick, and accurate procedure which could substitute for stereotactic methods. The accurate catheter position provided by real-time observation enables an effective aspiration and drainage of hematomas.

Effect of Body Habitus on Radiation Dose During CT Fluoroscopy-Guided Spine Injections

This study investigated the degree to which body habitus influences radiation dose during CT fluoroscopy (CTF)-guided lumbar epidural steroid injections (ESI). An anthropomorphic phantom containing metal oxide semiconductor field effect transistor (MOSFET) detectors was scanned at two transverse levels to simulate upper and lower lumbar CTF-guided ESI. Circumferential layers of adipose-equivalent material were sequentially added to model patients of three sizes: small (cross-sectional dimensions 25×30 cm), average (34×39 cm), and oversize (43×48 cm). Point dose rates to skin and internal organs within the CTF beam were measured. Scattered point dose rates 5 cm from the radiation beam were also measured. Direct point dose rates to the internal organs ranged from 0.05-0.11 mGy/10mAs in the oversized phantom, and from 0.18-0.43 mGy/10mAs in the small phantom. Skin direct point dose rates ranged from 0.69-0.71 mGy/10mAs in the oversized phantom and 0.88-0.94 mGy/10mAs in the small phantom. This represents a 180-310% increase in organ point dose rates and 24-36% increase in skin point dose rates in the small habitus compared with the oversize habitus. Scatter point dose rates increased by 83-117% for the small compared to the oversize phantom. Decreasing body habitus results in substantial increases in direct organ and skin point doses as well as scattered dose during simulated CTF-guided procedures. Failure to account for individual variations in body habitus will result in inaccurate dose estimation and inappropriate choice of tube current in CTF-guided procedures.

Pneumonia occurring after injection of Lipiodol to localize pulmonary nodules before fluoroscopy-aided thoracoscopic resection

We report the case of a 33-year-old man with a testicular tumor and multiple lung metastases. After high orchiectomy, chemotherapy was administered. Subsequently, fluoroscopy-assisted thoracoscopic resection was performed for pulmonary lesions that had decreased in size after the chemotherapy but had persisted. Because four pulmonary lesions were too small to detect by fluoroscopy during the operation, Lipiodol marking was done before thoracoscopic resection. Sixteen days after the surgery, pneumonia after Lipiodol injection occurred on the lung contralateral to that injected with Lipiodol. Pneumonia improved rapidly after intravenous infusion of antibiotics.

Impact of physician practice on patient radiation dose during CT guided biopsy procedures

PURPOSE

Patient radiation dose during Computed Tomography (CT) guided biopsy procedures is determined by both acquisition technical parameters and physician practice. The potential effect of the physician practice is of concern. This study is to investigate the effects of those intangibles on patient radiation dose.

METHODS

Patient radiation dose from 252 patients who underwent CT guided biopsy from 2009 to 2010 were retrospectively studied. Ten physicians who used conventional intermittent shots, low mA dose saving feature, or both were included in the study. The patient dose reports were retrieved and the total dose length products (DLPs) were analyzed. Linear regression analysis performed between various variables and reported dose. Patient detriment index (PDI) was developed, which sets threshold (standard of practice) for comparing physician practice with their peers. Odds ratio was calculated to determine odds of a group of patients receiving dose above threshold when compared to another group.

RESULTS

Median DLP among ten physicians was 1194 mGy-cm. There was a significant difference (p< 0.01) between reported DLPs doses when physicians used dose saving feature vs. when feature not used (539.8 ± 169.4 mGy-cm vs. 1269.7 ± 659.0 mGy-cm). In general, physicians who used dose saving feature had lower relative PDIs (< 1) compared to the PDIs (> 1) without the dose feature. Odds ratio estimate of 7.7 at 95% confidence level indicates that the odds of a group receiving a high dose depends on practitioner.

CONCLUSION

Adjustments of practice habits, use of dose saving features or both may be needed to improve patient care for CT biopsy.